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Topic Review (Newest First)

02-13-2013 09:50 AM

Mr. P-Body

If it is indeed a '66, that "WW" means a 335 HP 389 (1 4-bbl), manual transmission. The date code is by the distributor and looks like a "tab" that is screwed down, where it's actually "cast in" with four digits. The first digit is the month (A=Jan, B=Feb, etc.). The next two digits are the day of that month. The last digit is the last digit of the year it was cast. An example would be "H205" would be a '66 block (next year's models start in July) cast on August 20th, 1965. That would be an "early build" for the '66 model year.

Also, count the number of expansion plugs in the side of the block. This is how we "narrow it down". A 389 has 2 plugs per side. A 400 (could have a similar casting date, ten years newer) has 3. Logical deduction gets us where we "need to be". And according to the database, that engine WOULD have "93" heads, as it IS a GTO code.

I saw a bumper sticker on Mini in `1970 that said that about Lucas, at Laguna Seca during the Monterey Grand Prix (Can Am cars WOW!!!). On the same "note", a friend, married to a British lady, drank an ice cold Coors (for me) while standing in front of a beefeater at Buckingham Palace on July the 4th, 1986, just for fun.

All joking aside, my father was stationed at Watton, 1942-45. He was a bombsight tech on B-17s and B-24s. In '95, he and Mom made it back for the 50th reunion. The town of Watton (I guess that's the nearby town) welcomed them to the point where they couldn't spend a nickel. Room, food, transportation, events, ALL "free" for American AAF vets! That's CLASS! Thank you to all Brits for the way you treated the greatest generation of Americans since The Revolution, and just maybe, EVER.

Jim

02-12-2013 07:24 PM

LATECH

X 2 with Bill. The casting number will be inside the valve cover area on the 66 and back heads, look for the last 2 numbers in the 7 or 8 digits that are cast into the head.That will be the number

02-12-2013 06:50 PM

WDCreech

Quote:

Originally Posted by UKstepside

lol Mr P-Body
The block has WW on it but no numbers can be found on the heads at all

The head number that you need to find will be cast on, not stamped.

Bill

02-12-2013 06:00 PM

gearheadslife

chevy cavilers and some colbalts have vac pumps, get one and have at it with a wild hair cam..
many 90's caddy's also have the pumps,,

Awesome info guys - many thanks im such a newbie at yank stuff but i learn fast
If it was a VAG or Subaru i'd be well away. lol.

Im happy to have a slighty rougher idle from a cam, it sounds just awesome. I need to find some headers foe it and make up a stainless exhaust as its stock just now and is shot. I also need to look into the rear end and decide what - if needed - axle to go for. i want it to be a good driver for long distance to shows all over the UK and be able to smoke from the lights

Andy

02-11-2013 09:00 AM

Mr. P-Body

If it is truly a "GTO" engine, the heads will be "93s". 92s were on all other 389s except GTO.

The Pontiac used the timing cover for the "front mount" in those days. The aluminum versions of later years still have the bolt provosinos, but I would hesitate to use one as a "mount' in a high-torque engine.

Pontiacs are very sensitive to compression versus fuel quality. Make certain your static ratio is reduced to under 9.5:1.

Comp offers the XE series for the Pontiac. The XE256H is probably what you're looking for. Decent idle, good low- and mid-range power. The "next one up" (XE262H) is the most popular grind we have for "stockers". Works very well in 389s with TriPower and stock exhaust.

Quick ID:
If the V8 engine in your GMC truck has front motor mounts, it is the original 1955-1959 Pontiac V8.
A 1960 - 1979 Pontiac V8 had side motor mounts and no provisions for front motor mounts. .

02-10-2013 09:48 AM

UKstepside

hi huys,
many thanks for the replys.
i'll get the info needed asap but might be a week or 2 as i need to get the truck picked up and brought to me so i can go over it properly to make sure she's sound & safe.

It is believed that its a GTO donk, but the numbers will confirm when i get them.
I do have big plans for her but as with most rodders, it wont happen over night

cheers again. Andy

02-10-2013 09:35 AM

LATECH

X 2 with Widetrack here.
Some more info is needed.
I would suspect the rear end gear is pretty low , like 3.56 or 3.73.
Kinda too low for a truly streetable ride with a poncho mill as the poncho mill makes more torque and can handle higher ratios much better.
Way kool that you have a GMC with a pontiac engine in it.
I would love to here more about it.

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